New substituted phenol-carboxylic acids and process of making same



Patented Dec. 20, 1932 UNITED STATES mm Q F ICE LEOPOLD LASKA AND OSKAR- HALLER, or oFrn-NBAe LoN-Tnnuvmm, GERMANY,

ASSIGNORS TO GENERAL ANILINEWVOBKS, I.L*C., OF NEW YORK, N. Y., A CORPORA- TION OF DELAWARE NEW SUBSTITUTED PHENoL-oAnBoxYLIo Aorns AND Pnoo'nss'or MAKING SAME No Drawing. Application filed March 19, 1931. Serial No. 523,934, and in Germany April 3, 1930;

Our present invention relates to substituted phenol-carboxylic acids and to a process of making them. 7

The process of manufacture in accordance with this invention comprises heating an alkali metal salt of a substituted phenol of the general formula: v

COOH

wherein X has the aforesaid significance.

Thus the process represents the rare case of a smooth formation of a 1.2.3.4-substituted benzene.

The new carboxylic acids are valuable intermediates for the production of dyestufi's. In order to further illustrate our inven tion the following examples are given, the

group. According to wateris distilled off, finally under reduced and all temperatures but we wish it to be Example 1 163 parts of v1,4-dichloro-2-hydroxybenzone are dissolved in 56 parts of caustic potash and 800 parts of water in an autoclave provided with a stirrer, and the water is distilled ofi, finally under reduced pressure, until the mass becomes entirely dry. Into the cold reaction mass carbon dioxide is intro 7 duced until a pressure of atmospheres is attained and the whole is heated at 140150 G. for-8 hours. After cooling, the mass is dissolved in hot water, the solution is filtered and the 1.t-dichloro-2-hydroxybenzene-carboxylic acid is precipitated from the filtrate by means of hydrochloric acid. When recrystallized from Water it melts at 187 C. The alcoholic solution of this acid yields a violet coloration after the addition of a di-- lute solution of ferric chloride.

The process may be applied in like manner to the sodium salt of 1.4-dichloro-2-hydroxybenzene.

Example? 142.5 parts of 4-inethyl-1-chloro-2-hy- "droxybenzene are dissolved in 66 parts of caustic potash and 500 parts of water in an autoclave provided with a stirrer, and thepressure, until the mass'becomes entirely dry. Into the cold reaction mass carbon dioxide is introduced until a pressure of 10 atmospheres is attained and the whole is heated v at 120-130 ,C. for lOhours. After cooling, the mass is dissolved in hot water, the solu tion is filtered and the -methyl-l-chloro-Q- hydroxybenzene-carboxylic acid is precipitated from the filtrate by means of hydro-- chlori'c acid." For further purification, it is that we are not limited'to the I comprises heating at a temperature of about 120 C. to 150 C. an alkali metal salt of a substituted phenol of the general formula:

wherein X represents chlorine or a methyl 1 group, with carbon dioxide at a pressure of about 10 to atmospheres.

2. A process for the manufacture of a new dichloro-phenol-carboxylic acid which comprises heating at a temperature of 140 C. to 150 C. an alkali metal salt of 2.5-dichlorophenol of the formula with carbon dioxide at a pressure of 40 atmospheres.

3. A process for the manufacture of a new chloro-methyl-phenol-carboxylic acid which comprises heating at a temperature of 120 C; to 130 C. an alkali metal salt of 2-chloro- S-methyl-phenol of the formula:

OH: with carbon dioxide at a pressure of 10 atmospheres.

1. As new compounds the substituted phenol carboxylic acids of the probable general formula:

OOOH.

wherein X represents chlorine or a methyl group, which compounds represent when dry nearly colorless substances, having a definite melting point, soluble in alkalies, showing when dissolved in alcohol a violet coloration after the addition of a dilute solution of ferric chloride. 5. As a new compound the dichloro-phenolcarboxylic acid of the probable formula:

CODE

which compoundrepresents when dry nearly colorless substance melting when recrystallized from water at 187 0., soluble in alkalies, showing whendissolved in alcohol a violet coloration after the addition of a dilute solution of ferric chloride.

6. As a new compound the chloro-methylphenol-carboxylic acid of the probable formula:

coon

which compound represents when dry a nearly colorless substance melting when recrystallized from dilute alcohol at 174 0., soluble in alkalies, showing when dissolved in alcohol a violet coloration after the addition ofa dilute solution of ferric chloride.

In testimony whereof, we afiix our signatures.

' LEO'POLD LASKA.

OSKAR HALLER. 

